The present invention pertains to an electrical cable and, in particular, a circuitized electrical cable and a method for assembling a circuitized electrical cable.
Electrical cables such as flat ribbon cables are typically connected at each end to a component. The cable may be stripped at each end and the bare conductors attached directly to the component or an electrical connector may be mounted to the end of the cable and the connector plugged into a component. As the cables have also been used in more and more complex systems, additional devices have been added intermediate the ends of the cable. In the most common form, insulation displacement contact (DC) connectors are added to the cable at any point by having IDC contacts with sharp edges pierce the insulation of the cable and make electrical contact with the conductors of the cable. The IDC connectors generally have exposed female contacts for attachment of another device to the IDC connector. For example, U.S. Pat. No. 5,472,348 discloses the attachment of a terminator to an IDC connector mounted to flat ribbon cable. The terminator includes a housing having a printed circuit board mounted therein having circuitry and components mounted thereon to provide for the termination circuitry. Also mounted through the printed circuit board are contacts which mate with the female IDC connector mounted on the flat ribbon cable. In this way, the signal lines of the flat ribbon cable may each be individually altered according to the circuitry of the connector which is attached to the IDC connector mounted on the cable. However, the aforementioned system has the disadvantages in that multiple components must be manufactured and attached to the electrical cable requiring multiple steps and lengthy assembly time.
Further, data rates of cables continue to increase. For example, the promulgation of SCSI I, then SCSI II, then SCSI III has caused increase in density and speeds on cables and connectors. Such increases make the impedance levels of these systems more important. Generally, the greater the number of interconnects in an assembly, the greater the impedance and the slower the data rate. Therefore, it is desired for there to be a new, improved low impedance cable assembly.
Therefore, it is an object of the present invention to provide an electrical cable which may be circuitized quickly and inexpensively.
It is another object of the present invention to provide a circuitized electrical cable having an extremely low profile.
It is a further object of the present invention to provide for a method of circuitizing an electrical cable by mounting a circuit board directly thereto.
It is another object of the present invention to provide a cable assembly having controlled impedance mismatch.